1. Field of the Invention
The present invention relates to a method of producing non-oriented magnetic steel heavy plate having high magnetic flux density, for magnetic cores used under DC magnetizing conditions and for magnetic shielding.
2. Description of the Prior Art
With the progress in recent years of elementary particle research and medical instruments, devices using magnets are being used in large structures and there is a demand for improved performance in such structures. Numerous electrical steel sheets having good magnetic flux density have been provided, especially silicon steel sheet and electrical mild steel sheet.
However, with respect to their use as structural members, there have been problems with the assembly fabrication and strength of such materials, and this has necessitated the use of steel heavy plate. So far, such electrical steel heavy plate has been produced using pure iron components, as in JP-A No. 60(1985)-96749, for example.
However, with the increase in the size and performance of the devices concerned, there is a strong demand for steel materials with better magnetic properties, especially a high magnetic flux density in a low magnetic field, for instance 80 A/m. With the known steel materials, high magnetic flux density in a low magnetic field of 80 A/m cannot be obtained stably.